Unexpected Results from UTHSC NIH-funded Look AHEAD Study

NIH-funded Look AHEAD Study at The University of Tennessee Health Science Center Did Not Reduce Cardiovascular Events in Obese Adults with Type 2 Diabetes

Study Found Numerous Other Health Benefits of Modest Weight Loss

Memphis, Tenn. (June 25, 2013) – The results are in for Look AHEAD, an interventional study that focused on getting overweight and obese adults with type 2 diabetes to lose weight and increase physical activity to determine if these changes could prevent heart attacks and strokes. But the results are not what researchers expected.

The Look AHEAD (Action for Health in Diabetes) study results were presented this month at the American Diabetes Association’s 73rd Scientific Sessions ®. Look AHEAD was a two-armed randomized trial conducted in 16 centers across the United States, with more than 5,000 overweight or obese adults aged 45-76 years diagnosed with type 2 diabetes. The University of Tennessee Health Science Center (UTHSC) Department of Preventive Medicine and the Division of Endocrinology became a site for the study in 1999. UTHSC was originally scheduled to continue the study through 2014. More than 300 people in the Memphis area took part in Look AHEAD.

Funded by the National Institutes of Health (NIH), the study assigned participants to one of two interventions: lifestyle (involving increased physical activity and weight loss), or diabetes support and education (involving three counseling sessions per year on nutrition, physical activity, and social support). Last fall, the NIH discontinued the study early because the study intervention did not appear to prevent heart attacks and strokes. Nevertheless, study participants realized weight loss that resulted in other significant health benefits — lower blood pressure, decreased blood sugar and reductions in cholesterol.

Some Look AHEAD participants were followed for up to 11.5 years, with a median follow-up of 9.6 years at the time the intervention ended. The primary goal was to determine whether the intensive intervention would reduce the risk of cardiovascular disease and death, according to Karen C. Johnson, MD, MPH, professor and interim chair of Preventive Medicine and PI (principal investigator) of the Look AHEAD study at UTHSC. The Co-PI on the study was Abbas E. Kitabchi, PhD, MD, professor in the Division of Endocrinology, UTHSC College of Medicine.

Though participants in the intensive lifestyle intervention group initially lost 8.6% of body weight and maintained a loss of 6% of body weight at the end of intervention, which was better than researchers expected, the intensive lifestyle group did not reduce their risk of cardiovascular disease and death, or the level of LDL-cholesterol (the so-called “bad” cholesterol) compared to the group that received diabetes support and education. The support and education group lost 0.7% initially and 3.5% at the end of intervention.

There were numerous possible explanations for the unexpected results, including the greater use of medications to lower LDL cholesterol in the comparison condition, which may have minimized any difference between the groups. The study cannot rule out the possibility that greater weight losses might impact cardiovascular risk. However, the intensive lifestyle intervention group did experience other benefits when compared to those in the comparison group, including reducing the risk of kidney disease, self-reported retinopathy, and depressive symptoms. Other benefits included an improved physical quality of life and reduced annual hospital rates and costs. Lifestyle intervention also produced greater reductions in A1C (a three-month average of blood sugar scores) and greater initial improvements in fitness and all cardiovascular disease risk factors except LDL cholesterol.

“This study shows that overweight and obese adults with type 2 diabetes can lose weight and keep it off, with many important health benefits,” said Griffin P. Rodgers, MD, director of the National Institute of Diabetes and Digestive and Kidney Diseases, part of the NIH. “It reinforces the recommendation that overweight and obese people with type 2 diabetes should increase their physical activity levels and lose weight to improve their health.”

As Tennessee’s only public, statewide academic health system, the mission of the University of Tennessee Health Science Center (UTHSC) is to bring the benefits of the health sciences to the achievement and maintenance of human health, with a focus on the citizens of Tennessee and the region, by pursuing an integrated program of education, research, clinical care, and public service. Offering a broad range of postgraduate and selected baccalaureate training opportunities, the main UTHSC campus is located in Memphis and includes six colleges: Allied Health Sciences, Dentistry, Graduate Health Sciences, Medicine, Nursing and Pharmacy. UTHSC also educates and trains cohorts of medicine, pharmacy and/or allied health students — in addition to medical residents and fellows — at its major sites in Knoxville, Chattanooga and Nashville. Founded in 1911, during its more than 100 years, UT Health Science Center has educated and trained more than 56,000 health care professionals in academic settings and health care facilities across the state. For more information, visit www.uthsc.edu.